Lots of people think that, but it's not true. The competition for studio work is extraordinarily intense--labor supply significantly exceeds demand--and compensation reflects that. If you think living in the Bay Area is tough as a programmer, try it when you're making a quarter of an engineer's salary (and Pixar, unlike the major L.A. studios, is not unionized). Though I can't speak to Pixar specifically, generally most such positions are on contract--when the production's done, so is the budget for staffing--so you're bouncing from studio to studio constantly looking for work.

Besides, a lot of a production like this is essentially just writing code. I've had multiple industry artist friends tell me that, if they could go back and start over, they would have done computer science as a career and art on the side.